It is well known to provide a machine for successively performing several operations on various sheet elements. For example, operations on an envelope might include flapping, inserting, moistening and sealing, whilst operations on one or more sheets might include collating, folding and inserting into an envelope. It is further known to provide a machine which collates several sheets of paper into a bundle, folds the bundle, places an insert, such as a leaflet or booklet into the bundle, provides an envelope which is held open, inserts the folded sheets into the envelope, moistens the envelope and seals it, before ejecting the envelope into a receiving tray or bin. Each of these operations is distinct and requires a separate and unique processing region within the machine in order to successfully and repeatably carry out the required operation on the respective element. As a result, folder/inserter machines of the type described hereinbefore are typically large and complicated to program.
Recently, there have been moves towards reducing the size of such folder inserter machines in order to make them more accessible to smaller businesses, such as SOHO (small office/home office) operations. In order to be successful in this environment, the folder/inserter must occupy a small footprint (i.e. the area of floor/desk-surface occupied), perform reliably, and be easy to control without requiring specialist training.
GB-A-2380157 discloses a small office folder/inserter having two trays, and for storing sheets to be folded and the other for storing inserts to be inserted into the sheets. One location is specified for folding said sheets, another location for placing the insert into the folded sheets, and a further location for inserting the folded bundle into an envelope. The machine further comprises a location for storing envelopes, means for opening said envelopes and holding the envelopes open to receive the folded bundle at the inserting location, a section for moistening the flap of the envelope and a section for closing the flap of the envelope to seal it and ejecting the envelope to a receiving tray. Because of the small size and compactness of the machine, it is suitable for performing only a limited number of cycles in a given time period, i.e. it does not have a very high-volume throughput. Further, such machines can lack versatility, since they are suitable only for performing the respective feeding, folding, inserting, envelope opening, envelope moistening and sealing operations on a limited range of sizes of sheets/inserts.
Large organisations, such as banks, telephone companies, supermarket chains and the government, for example, are often required to produce extremely large throughputs of specifically-addressed mail to a regional or national audience. Machines capable of producing the high volumes required, whilst simultaneously accurately ensuring that the correct content is sent to the individual recipients, are typically very large, often occupying an entire warehouse. By contrast, existing small office equipment is typically capable of producing mailshots for a few hundred to one or two thousand addressees.
Demand, therefore, exists for a machine of intermediate production capacity, typically for small to regional businesses, which does not occupy a vast quantity of the available office space. Particularly in large cities, office space is charged at premium rates for each square metre. As such, the cost of running and maintaining a folder/inserter will also comprise the cost of renting the office space which it occupies.
For folder/inserter apparatuses intended for small and medium sized businesses, it is at least desirable, if not necessary, for the machine to be able to accommodate a range of different materials. For example, it will be necessary to accommodate different thicknesses of sheet element, as well as different sizes and numbers thereof. Similarly, any materials to be inserted within a folded package might range from a compliments slip to an entire booklet, including inserts of unconventional size or shape. It is also advantageous for such machines to be able to accommodate different sizes of envelopes, such as A4 and A5, depending on the material to be inserted thereinto.
In the actuation of a gate within a paper path. It is often required to resist large forces when in the closed position. This can be done using a powerful actuator such as a solenoid, capable of resisting the applied force. Alternatively, a cam can be used to push the gate closed using a suitable profile to remove or reduce the load to the driving motor. However, if any of these are actuated closed while a piece of paper is passing the gate location, the large forces generated can cause significant damage or paper jams. This is classed as a high severity in a Failure Mode and Effect Analysis and is very dissatisfying to an operator.
The invention utilises an actuating motor or solenoid to push the gate open against a light spring force pulling the mechanism closed. An over-centre feature of the mechanism means that, once closed, the mechanism is locked against forces applied to the gate by its own mechanical strength. As it is only a light spring pulling the mechanism closed, accidental operation during the passing of a sheet of paper leads to little or no damage to the sheet, and no jam.
According to one aspect of the present invention, there is provided a stopping device for stopping the travel of sheets along a sheet path, the stopping device comprising: a gate member movable between an interference position in which it prevents the travel of sheets along the sheet path, and a release position in which sheets are permitted to travel along the sheet path; and a lock-out means operable to lock the gate member in the interference position against forces substantially in the direction of travel of sheets along the sheet path.
According to a second aspect of the invention, there is provided a method of stopping the travel of sheets along a sheet path, the stopping method comprising: moving a gate member from a release position in which sheets are permitted to travel along the sheet path to an interference position in which it prevents the travel of sheets are permitted to travel along the path; and locking the gate member when in the interference position against forces substantially in the direction of travel of sheets along the sheet path.